Was Jairus' daughter alive when Jesus was approached?

She was already dead.

While he spake these things unto them, behold, there came a
certain ruler, and worshipped him, saying, My daughter is even now
dead: but come and lay thy hand upon her, and she shall
live. Matthew 9:18

She was still alive.

And, behold, there cometh one of the rulers of the synagogue,
Jairus by name; and when he saw him, he fell at his feet, And besought
him greatly, saying, My little daughter lieth at the point of death:
I pray thee, come and lay thy hands on her, that she may be healed;
and she shall live. Mark 5:22-23

And, behold, there came a man named Jairus, and he was a ruler
of the synagogue: and he fell down at Jesus' feet, and besought him
that he would come into his house: For he had one only daughter, about
twelve years of age, and she lay a dying. Luke 8:41-42